Commit Graph

6 Commits

Author SHA1 Message Date
Boris BREZILLON ceb12f9398 pwm: atmel-tcb: fix max time computation for slow clk source
Use the the tcb counter width to compute the maximum time that can be
represented using the slow clock source instead of the static 16 bit width.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-09-19 14:04:32 +02:00
Boris BREZILLON f3a82170ae pwm: atmel-tcb: add missing clk source config
Clock source changes are never applied to the CMR register.
This may lead to wrong period/duty cycle configuration.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-09-19 14:04:24 +02:00
Thierry Reding 3dd0a90947 pwm: Fill in missing .owner fields
Some drivers don't set the .owner fields of the struct device_driver or
struct pwm_ops, which causes the module usage count to become wrong.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-12 13:18:29 +02:00
Boris BREZILLON 8796f9c565 pwm: atmel-tcb: prepare clk before calling enable
Replace clk_enable/disable with clk_prepare_enable/disable_unprepare to
avoid common clk framework warnings.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-12 12:51:44 +02:00
Axel Lin 83c80dc535 pwm: atmel-tcb: Add .owner to struct pwm_ops
Add missing .owner of struct pwm_ops. This prevents the module from being
removed from underneath its users.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-04-02 11:29:22 +02:00
Boris BREZILLON 9421bade07 pwm: atmel: add Timer Counter Block PWM driver
This patch adds a PWM driver based on Atmel Timer Counter Block. The
Timer Counter Block is used in Waveform generator mode.

A Timer Counter Block provides up to 6 PWM devices grouped by 2:
* group 0 = PWM 0 and 1
* group 1 = PWM 2 and 3
* group 2 = PMW 4 and 5

PWM devices in a given group must be configured with the same period
value. If a PWM device in a group tries to change the period value and
the other device is already configured with a different value an error
will be returned.

This driver requires device tree support. The Timer Counter Block number
used to create a PWM chip is given by the tc-block field in an
"atmel,tcb-pwm" compatible node.

This patch was tested on kizbox board (at91sam9g20 SoC) with pwm-leds.

Signed-off-by: Boris BREZILLON <linux-arm@overkiz.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
2013-01-08 16:52:10 +01:00